Spring powered toy cars utilizing wheels as a means of locomotion are well known. Also, it is well known to utilize mechanical legs to move toys along a surface. For example, U.S. Pat. No. 5,423,708 (the xe2x80x9c""708 patent) discloses a robot toy which simulates the movement of a spider. The robot toy includes four pairs of operative cooperating legs located on either side of the main frame of the robot. The articulated robot legs disclosed in the ""708 patent are configured so that alternate legs on each side of the toyxe2x80x94mirrored legsxe2x80x94are aligned in a down position so as to provide balancexe2x80x94and so reduce wobbling of the robotxe2x80x94when the toy is moving. While the ""708 patent discloses a toy with mechanical legs on either side of a main frame, there is no means of locomotion provided and/or situated between the right and left robot legs. Also, the inherent xe2x80x9cbalancingxe2x80x9d the device provided by the afore-mentioned alternate mirrored configuration of legs generally maintains the robot in an upright (balanced) position as the toy moves forward. Such a balancing effect prevents a change in attitudexe2x80x94from upright to canted to the left or rightxe2x80x94which might otherwise allow the device to engage dips and depressions while traversing uneven terrain. Therefore, if the ""708 robot should lose contact with trackable ground on either the right or left side of the device due to, for example, uneven terrain, locomotion is compromised. Furthermore, the outboard position of the legs extending from the ""708 robot, are unable to engage terrain directly under the toy. Therefore, if the device attempts to traverse terrain demonstrating a peak or ridge oriented in line with the long axis of the toyxe2x80x94and direction of travelxe2x80x94, the outboard legs may become hopelessly suspended, xe2x80x9cbeachedxe2x80x9d upon the ridge directly under the frame of the toy and unable to make further progress. Also, although the articulated robot legs of the ""708 device may provide suitable propulsion on various surfaces demonstrating adequate friction and/or demonstrating a texture allowing engagement of the robot legs, the small xe2x80x9cfootprintxe2x80x9d provided by the disclosed legs may compromise movement on hard, smooth surfaces.
Conventional spring or electric motor driven toys utilizing outboard wheels in a similar manner as full size automobiles provide excellent movement and speed on hard, smooth surfaces. The term xe2x80x9coutboardxe2x80x9d as used throughout this specification and claims in regard to wheels, legs or other device parts refers to the lateral position of said parts in relation to the main frame of any such device. Therefore, outboard device legs and/or wheels would be generally located outside of the confines of extension of the frame or proximal to the lateral (right or left sides) of such devices. The term xe2x80x9cinboardxe2x80x9d as used throughout this specification and claims in regard to wheels, legs or other device parts, refers to the relative position of said parts as being within the confines and lateral extension of such device main frames. The xe2x80x9cinboardxe2x80x9d location of such propulsion means would include locating such means at or about the longitudinal axis (midline) of such devices as well as locations between said midline and the lateral extent of the device frame.
Wheeled toy vehicles may also be provided with texturedxe2x80x94knobbyxe2x80x94tires in order to increase traction when utilized on irregular surfaces. However, wheeled vehicle may not exhibit sufficient traction to negotiate highly irregular surfaces which may be negotiated by devices such as the ""708 robot. Also, such wheeled toys, unless provided with sufficient ground clearance, may be likewise xe2x80x9cbeachedxe2x80x9d by an elevated ridge or other obstruction located directly under the toy and medial to such wheels.
It would be highly advantageous to provide a self-propelled toy which provided the advantages of both wheels and leg like locomotion means so as to maximize said toys ability to negotiate a wide variety of terrain. It would be further advantageous if said toy could exhibit both outboard and inboard means of locomotion in order to increase the likelihood of contact and traction of either means of locomotion with irregular and uneven terrain. It would be still further advantageous if said self-propelled toy were provided with a means to vary the attitude thereof, thereby alternating maximum contact of legs and or wheels located on opposite sides of said vehicle.
Now in accordance with the present invention a self-propelled toy is disclosed wherein locomotion is provided by both outboard legs as well as at least one inboard wheel. The self-propelled toy of the present invention is comprised of a frame having a front terminus, a back terminus, a right side, a left side, a top and a bottom. Paired, mirror image axil receiving holes aligned in both fore/aft as well as inferior/superior position are provided within and through the right and left sides of the frame. A plurality of leg members, rotatably mounted within said paired, mirror image receiving holes, extend laterally beyond the left and right sides of the frame, in an outboard configuration. Each such leg member includes a central axil segment, extending through and beyond the pair of mirror image receiving holes. Lateral to said axil segment, the leg member includes a bend of from about 80 to about 100 degrees, in regard to the longitudinal axis of the axil segment, so as to form two leg segments on either side of said axil segment. The leg segments are advantageously selected to be of a sufficient length so as to extend beyond the bottom of the frame during the below-described rotation of the leg member. The axil segment, medial to said bend is substantially straight as is the leg segment, distal to said bend. However, in certain preferred embodiments of the present invention, the leg member may additionally include, distal to the leg segment, a foot segment, just distal to a further 80 to 100 degree bend. The foot segment serves, as discussed in further detail below, to increase the surface area of contactxe2x80x94or xe2x80x9cfoot printxe2x80x9dxe2x80x94of the leg member as said member, periodically, comes in to contact with terrain below the toy to provide traction and locomotion. The paired axil receiving holes through which the leg members are mounted, may be advantageously positioned and oriented in close approximation to the bottom of the frame so as to facilitate periodic contact of the leg or foot segments with terrain under the toy, as well as to provide superior ground clearance. A leg drive gear is mounted, medial to the right and left side of the frame, upon the axil segment. The drive gear is configured and adaptedxe2x80x94is of a size and includes a tooth arrangementxe2x80x94so as to enable the leg drive gear to mesh and engage the below-described transfer gears so as to transfer torque and rotation to and between leg members for propulsion of the device.
At least one inboard main drive wheel is rotatably mounted within the confines of the left and right side of the frame, said wheel extending beyond the bottom portion of said frame. The main drive wheel, as discussed below, provides an additional means of propulsion (inboard wheel propulsion) through contact, rotation and traction against terrain under the toy. The main drive wheel is configured so as to include circumferentially located gear teeth so as to provide a means of transferring torsional force and rotation from a motor to the leg members (outboard foot propulsion) either by directly engaging a proximal leg drive gear or indirectly, via a transfer gear/unit, speed control gear or combinations thereof as discussed in greater detail, below. The gear teeth of the main drive wheel (or as it is also described herein xe2x80x9cthe main drive gearxe2x80x9d) also act as a means of increasing traction of the wheel against terrain. A motor unit, utilizing a drive means, such as, for example, a coil spring motor, battery powered electric motor or solar powered electric motor, provides torsional power to the toy. For example, a spring drive unit and main drive wheel may be advantageously mounted upon a main drive axil. The main drive axil is advantageously and rotatably mounted through a pair of mirror image axil receiving holes. Embodiments of the present invention utilizing spring drive motors may advantageously include wind handles located at distal termini of the main drive for providing power (winding of) to the spring motor. Upon winding of the spring motor, stored torsional power is applied by the spring motor in order to rotate the main drive axil, which, in turn, rotates the drive wheel.
As described above, the drive wheel is advantageously configured to extend beyond the inferior (bottom portion) extent of the frame so as to enable engagement of terrain under the toy. The drive wheel is also advantageously provided with gear xe2x80x9cteethxe2x80x9d as are all of the gears utilized herein. The teeth of the drive wheel enhance the ability of the wheel to be utilized as a means of propelling the toy. In addition, the drive wheel is, in certain preferred embodiments of the present invention, especially configured and adapted (includes gear count and size) to mate with and rotate a transfer gear mounted upon a transfer axil proximate to the main drive axil. The transfer axil, similarly mounted within a pair of mirror image axil receiving holes, positions the transfer gear so as to engage both the main drive wheel (and mate with the teeth thereupon) as well as to mate and engage with a leg drive gear. The present invention contemplates the use of at least two leg members. However, regardless of the number of leg members utilized, the present invention contemplates the use of a transfer unitxe2x80x94a transfer gear mounted upon a transfer axilxe2x80x94in order to transmit torsional force between/among said leg members. Thus, the main drive wheel, upon engaging and rotating a transfer gear, enables rotation of all leg members included therein via the transfer gear unit(s) coupling all such leg drive gears.
Alternatively, a speed control unit, comprised of a speed control axil, mounted within a pair of mirror image axil receiving holes, and a speed control gear mounted thereupon, may, in certain preferred embodiments, be interposed between the main drive wheel and the proximate transfer unit or leg drive gear. The speed control unit serves to control the rotational speed of the leg members. In such embodiments, the speed control unit is positioned so that the speed control gear mates, meshes and engages with the main drive wheel. Rotational speed transferred to the leg members via the transfer units mayxe2x80x94in such embodimentsxe2x80x94may be increased, or decreased, by interposing a speed control gear between the drive wheel and the transfer gearxe2x80x94in embodiments interposing a transfer gear between the main drive gear and proximal leg drive gearxe2x80x94and by selecting gear ratios, counts and sizing so as to attain such desired speed control. The use of gear configuration to control speed is well known to the art.
In addition to speed control units, other regulatory means, such as, for example, regulatory balance units utilizing weights may be utilized in order to regulate and control toy performance. The use of balance weights and other such devices to control spring powered devices is also well known to the art.
As discussed above, each leg member includes a straight axil segment extending through and beyond said paired mirror image receiving holes and beyond the lateral extension of the frame. After extending beyond the right and left sides of the frame and mounting holes therein, the leg members are bent at an approximately 80-100 degree angle. Thereafter, the leg members may advantageously include a further 80-100 degree bend so as to define a xe2x80x9cfoot likexe2x80x9d foot segment in order to obtain broader contact with a surface to be traversed. The leg members are advantageously configured so that the leg segments at terminal ends of each such member are in diametric xe2x88x92180 degreexe2x80x94circumferential diametric relation so that, for example, when the leg segment at one terminus of a leg member is perpendicular to the longitudinal axis of the frame and directed downward, against the terrain below, the leg segment at the opposite terminus is also perpendicular to the longitudinal axis of the frame, but oriented upward and over the toy. Such orientation is advantageous in causing the toy to wobble, to a certain extent during locomotion. Such wobbling allows the device to engage depressions in terrain otherwise beyond the xe2x80x9creachxe2x80x9d of the leg members when the device is perfectly balanced. It is preferred that the plurality of leg members are mounted and aligned within the frame so that none of the leg segments on either side of the frame are in circumferential alignment. A xe2x80x9cstaggeringxe2x80x9d arrangement which provides, for example, for a 90 degree rotational disparity between sequential leg segments on either side of the toy may be advantageously selected so as to increase the afore-mentioned shifting in device attitude (tilting to the left and right relative to the direction of travel during toy movement).
Each of the leg members includes a drive gear mounted upon the axil segment. Transfer gears, mounted upon transfer gear axils, are provided to engage said drive gears and thereby transfer rotational power between said leg members, while also maintaining the afore-mentioned circumferential relationships between said leg members and the foot like portions extending therefrom. The transfer gear axils are also rotatably mounted within paired, mirror image axil receiving holes in the right and left sides of the frame.
In a preferred embodiment of the present invention, the foot-like segment of the leg members may be coated and/or covered with a resilient material such as, for example, a rubber or plastic material, so as to provide still further traction.
As discussed above, at least one inboard drive wheel, rotatably mounted within the right and left confines the frame, extends below the frame so as to enable engagement of terrain below the device as an additional means of locomotion. Said drive wheel also includes a plurality of gear teeth of such a number and configuration as to enable engagement of the above described transfer gear or, in alternate embodiments, a speed control gear. Wind handles, located a distal termini of, for example, a spring motor, may be utilized to energize the spring motor as well as a further means of locomotion. For example, after winding the toy, the device may be placed on a surface. Thereafter, as the spring motor transfers rotational force back to the main drive axil, the wind handles located on distal ends thereof, also rotates and thus may provide an additional means of propulsion.
By utilizing the aforementioned combination of at least one inboard drive wheel and a plurality of leg means aligned so as to cause xe2x80x9cwobblingxe2x80x9d of the device, the self-propelled toy of the present invention in able to continue movement across uneven terrain. In instances wherein the device is positioned upon a high ridge, with depressed areas to either side of the toy, the at least one inboard drive wheel provides continued locomotion. In those instances wherein the terrain is so irregular as to obviate the use of a drive wheel, the foot-like projections of the leg means provide continued locomotion. In those instances where the terrain to either side of the toy is uneven, the wobbling effect thereof allows the device to tilt so as to enable contact of the foot-like projection with terrain for continued progress.